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View Full Version : Concorde RC RG well, concorde-ish


burkefj
06-06-2016, 02:51 PM
Sunday it was 100 degrees out so stayed indoors for the most part. I've always wanted to do a concorde but never have...so I gave it a shot. I started with the tubes/coupler/cone from the Estes Cosmic Interceptor. For the fuse, I angled the rear of one of the tubes with a cut to simulate the tapered concorde rear. I inset the motor tube at the bottom of the cutout, (Motor tube is right above the wing and even with the TE). I was limited on how much of an angled tail I could leave sticking out the back since my tubing was a set length and I knew I had to have sufficient forward length to avoid adding nose weight. I used two spare 1" wide body tube pieces I had to lengthen the center section 2" and left 3" to the rear of the wing as a compromise. I Joined the two body tube pieces and the two main body tubes using a coupler.

I used the basic wing planform from my Arc-Light kit, I adjusted the front of the wing and wingtip shape and mounted the wing on the bottom of the tube. I knew the added wingtip area would move the CG back about 3/8" which would help cg. I slotted and installed a concord-ish vertical tail which was large enough to give me lateral stability. I added some support gussets in the wing/tube joint to give extra gluing area. The receiver is mounted at the front of the body tube using velcro, and the single cell lipo is mounted just inside the shoulder of the nose cone. I removed the base of the nose cone so I could mount the battery inside. Rail buttons are mounted on the bottom of the model.

For asthetics, I mounted the servos on the bottom of the wing, but made some foam blocks that help keep the servo arms from contacting the grass/ground. The servo wires route into the body tube and use servo extensions to get forward to the receiver.

I made a little template for the windows/doors and did those with a sharpie and then used some vinyl trim to hand create the tail stripes and cockpit windows.

for flight I started with 1/8" of downtrim for boost and 3/8" up for glide.

I did three test flights yesterday evening in about 90 degree temps in 8-9 mph wind and it boosted really nicely, needed to adjust glide trim down to 1/4". I had tried some metal gear turnigy servos but they turned out to have random centering problems so I swapped them for some spare hs-55's I pulled from another model.

Three beautiful hands off boosts this morning in dead calm air, perfect glide and easy flare on landing, estimated 1 minute flights. I was concerned about the motor potentially burning the inside top of the angled rear end, but turned out to be a non issue.

40" long, 23.5" wingspan 11.675 ounces rtf.

Frank

luke strawwalker
06-06-2016, 06:24 PM
Very nice... OL J R :)

ghrocketman
06-06-2016, 09:57 PM
Sounds like you are having problems with Turnigy products as well.
Wondered about their servos...I have had NOTHING but problems with their LiPo packs for micro to medium-sized electric R/C aircraft. Enough problems as to capacity and life where I have forever banned purchasing their products, and reccommend others do the same.

AstronMike
06-07-2016, 11:44 AM
Was wondering when you'd get around to a Concorde-ish sort!

This is similar to the BT-70 Concorde I flew the heck out of a few years ago, primarily on E20s. That used a regular 34" BT-70, with a rolled paper cone for the NC. Angled rear tube, as well, no charring issues there. Readiboard wings/tail, and BT50 pod. Great flyer, need to make another.

Thinking of making a 3" Concorde, using two ply standard foamboard, as a reasonable HPR glider, without being too large. I motors seem to be the best 'cross' between size/power, and affordability. Yeah, this will be old school Free Flight, so it'll probably glide nice and straight.

Seems you're getting mileage out of those Cosmic Interceptor parts....wonder if I should get on board? How heavy is the NC, and is that a BT70 or 2" heavy walled tube?

burkefj
06-07-2016, 12:37 PM
They are a bit thicker than super thin wall, but are not thick.

The two 13.5" long 2" tubes and a 4" coupler weigh 2 3/4 ounces, the nose cone with the bottom removed weighs 1 3/8 oz. the cone is 11" long without the shoulder so it will make a 38" long model.

The kit does include an extra coupler and a 1" long body tube piece so on one model I inserted the spare coupler part way into the rear of the model and glued the 1" long piece on the end and was able to stretch the length 1 or two inches.


As a reference two 17" long lightweight bt-80 tubes from bms with a 4" coupler weigh 3 3/4 ounces. The lightweight cone I get from sirrius rocketry weighs 1 3/4 ounces with the base removed.

Frank


Was wondering when you'd get around to a Concorde-ish sort!

This is similar to the BT-70 Concorde I flew the heck out of a few years ago, primarily on E20s. That used a regular 34" BT-70, with a rolled paper cone for the NC. Angled rear tube, as well, no charring issues there. Readiboard wings/tail, and BT50 pod. Great flyer, need to make another.

Thinking of making a 3" Concorde, using two ply standard foamboard, as a reasonable HPR glider, without being too large. I motors seem to be the best 'cross' between size/power, and affordability. Yeah, this will be old school Free Flight, so it'll probably glide nice and straight.

Seems you're getting mileage out of those Cosmic Interceptor parts....wonder if I should get on board? How heavy is the NC, and is that a BT70 or 2" heavy walled tube?

stefanj
06-07-2016, 10:49 PM
I remember seeing Concordes flying over Nassau Community College on their way to JFK. Very cool project.

burkefj
06-09-2016, 10:21 AM
Ok, I relased this as a kit this morning...details on my site.

sandman
06-09-2016, 04:54 PM
I remember seeing Concordes flying over Nassau Community College on their way to JFK. Very cool project.

I was on a 777 in line to take off behind the British Concord back in 2006.

When the Concord floored it"s throttled directly in front of us, the noise opened most of our overhead compartments.

Very very loud!!

Blushingmule
06-10-2016, 11:54 AM
I was on a 777 in line to take off behind the British Concord back in 2006.

When the Concord floored it"s throttled directly in front of us, the noise opened most of our overhead compartments.

Very very loud!!

:-)

Gordy,

Back in the early 90's I was in Irving Texas visiting an old time hobby shop (MAL).
As I stepped out of the car I heard one hell of a noise...Concorde flying over from DFW airport.

Bob

burkefj
06-10-2016, 01:20 PM
Had three great flights in about 7 mph winds but completely crosswind from behind us so I had to do a bit of back and forth to land n the runway. Altimeter said 474 feet on the second flight which is all I recorded. Nice flyer. For some reason our rc club has gnome as a mascot so we hired him as an extra, as a little homage to the movie "Amelie"...

http://www.youtube.com/watch?v=aT5YdvBJKzg&feature=youtu.be

zog139
05-31-2020, 09:51 AM
Hi Frank, I finally finished my Stratodart. How do you store your models at home to minimize hanger rash ? I was thinking about some type of "mounts" that the rail buttons could sit in that could be mounted to the wall with 3M command adhesive strips. Has anyone found anything other than an actual 1010 rail that will hold a rail button ?

Jim

burkefj
05-31-2020, 10:38 AM
Jim, i use screw eyes in the ceiling, i then take a big paper clip and bend it so it has a loop on one end to go onto the screw eye, the other I bend into a hook shape that slides over the rail button and hang them inverted, sometimes I have to put two of them together to give me enough length so that the tail clears the ceiling depending on how far the tail sticks back and where the rail button is in the back.

ghrocketman
07-17-2020, 11:09 AM
Just watched your SR-71, X-15, and BOMARC rocket glider videos.
The SR-71 glided better than I expected, the X-15 glided about like it's full-scale counterpart (like a waxed BRICK), and the BOMARC was worse than I expected.
Cool videos.

burkefj
07-17-2020, 11:18 AM
The Bomarc has a lot of draggy bits, it is very flyable and flares nicely, I've never had any damage to the pods even landing on grass. You are right, models with small scale-ish wings don't glide very long:)

Frank


Just watched your SR-71, X-15, and BOMARC rocket glider videos.
The SR-71 glided better than I expected, the X-15 glided about like it's full-scale counterpart (like a waxed BRICK), and the BOMARC was worse than I expected.
Cool videos.

ghrocketman
07-17-2020, 11:48 AM
It looks like the BOMARC has more wing area than the X-15 but I forgot about the "draggy" pods.

burkefj
07-20-2020, 06:28 PM
The X-15 has more body lift due to the wider tube, but one thing you probably didn't realize, I was launching the the Bomarc on E-12 Aerotech motors which are a 34ns motor to keep the stress on the airframe and pods light, the X-15 is launching on F-24's which are a 47ns motor, the X-15 boosts to around 425' and the bomarc to closer to 300 at about 1/2 oz lighter liftoff weight.

I've flown the Bomarc on estes E-12's and it is very similar in altitude/glide time to the Aerotech E-12 at the same weight. In some videos my daugher/son zoom in as the rockets boost so it is hard to see how high they are really going. Here is an E-12 estes flight which doesn't zoom in and it looks higher but isn't really.

https://youtu.be/_OPaA993hcM

I've flown the Bomarc on older E-15 Aerotech motors, which were 40ns motors, here is one flight, it gets about 100' more altitude and about 10 seconds more glide time, similar to the X-15 on F-24's.

https://youtu.be/orFdH6xyaJM

In fact I just built a new bomarc version that cut the weight by 2 oz(14.25 oz rtf) that can fly on the E-6 motors and it now gets nearly identical flight times as the X-15.

It looks like the BOMARC has more wing area than the X-15 but I forgot about the "draggy" pods.